''Rhoiptelea'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus of flowering plants in the family Juglandaceae. It contains a single species, ''Rhoiptelea chiliantha'', commonly known as the horsetail tree. This genus was previously recognized in its own family, Rhoipteleaceae, but the

APG III system The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a f ...

of 2009 placed it in the

Juglandaceae The Juglandaceae are a plant family known as the walnut family. They are trees, or sometimes shrubs, in the order Fagales. Members of this family are native to the Americas, Eurasia, and Southeast Asia. The nine or ten genera in the family have ...

family. ''Rhoiptelea chiliantha'' is native to

southwest China Southwestern China () is a region in the People's Republic of China. It consists of five provincial administrative regions, namely Chongqing, Sichuan, Guizhou, Yunnan, and Xizang. Geography Southwestern China is a rugged and mountainous region, ...

and north

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

and lives at the elevation of 700-1600m in mountainous areas. The trees are wind-pollinated, the flowers arranged in large sagged

panicle In botany, a panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a p ...

s usually 32 cm long like horse tails, and the

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

is a small botanical nut with rounded wings. The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are pinnately compound and papery. The trees are usually 17 m high and with 40 cm diameter. It is a protected species of

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

References

Juglandaceae Monotypic Fagales genera Trees of China Trees of Vietnam Vulnerable plants Taxa named by Heinrich von Handel-Mazzetti Taxa named by Ludwig Diels {{Fagales-stub